The prior art comprises many folding carriage structures most of which are collapsible flat to a plain which is inconvenient for carrying. Although structures that are foldable to shape like a bundle of umbrella have been available nowadays. However the difficulty with these prior art devices is that the two side brace elements surround and confine on both sides resulting in a limited and uncomfortable seat position in which the passenger has to bend and curl in an unnatural manner without suitable arm rest place.